He was a younger son of Sir Thomas Rawlinson (1647-1708), Lord Mayor of London in 1705-6, and a brother of Thomas Rawlinson (1681-1725), the bibliophile. He was educated at St Paul's School, at Eton College, and at St John's College, Oxford. In 1716 he was ordained, but as he was a nonjuror and Jacobite the ceremony was performed by a non juring bishop, Jeremy Collier.
Rawlinson then travelled in England and on the continent of Europe, where he passed several years, making collections of manuscripts, coins and curiosities, in 1728 he became a bishop among the nonjurors, but he hardly ever appears to have discharged episcopal functions, preferring to pass his time in collecting books and manuscripts, pictures and curiosities. He died at Islington.
Rawlinson left his manuscripts, his curiosities, and some other property to the Bodleian Library; he endowed a professorship of Anglo-Saxon at Oxford, and was a benefactor to St John's College, Oxford.